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Mansouri, Alireza

0000-0002-7442-7539

Mayo Clinic

Department of Neurosurgery, Penn State Milton S. Hershey Medical Center, Hershey, PA.

Citations 13

Prognostic and Predictive Effect of Age in Molecularly Defined Lower-Grade Gliomas
Minniti, Giuseppe, Brown, Paul D. , Vogelbaum, Michael A. , Ballman, Karla V. , Mercurio, Ann, Siegelin, Markus D., Tuohy, Kyle , Mansouri, Alireza , Simonelli, Matteo, DeStephano, David, Shuryak, Igor , Roy, Soumyajit , Hervey-Jumper, Shawn L., Horowitz, David P. , Sisti, Michael B. , Bruce, Jeffrey N. , Canoll, Peter, Neugut, Alfred I. , Iwamoto, Fabio M., Cheng, Simon K. , Kachnic, Lisa A. , Kinslow, Connor J , Brown, Paul D , Vogelbaum, Michael A , Ballman, Karla , Mercurio, Ann , Tuohy, Kyle , Mansouri, Alireza , Touat, Mehdi , Dehais, Caroline , Dipasquale, Angelo , Grinband, Jack , Yu, James B , Walch, Henry , Parker, Mitchell I , Shuryak, Igor , Roy, Soumyajit , Gallitto, Matthew , Horowitz, David P , McKhann, Guy M , Bruce, Jeffrey N , Ostrom, Quinn T , Neugut, Alfred I , Pike, Luke R G , Cheng, Simon K , Kachnic, Lisa A , Mehta, Minesh P , Wang, Tony J C , Minniti, Giuseppe , Siegelin, Markus D. , Kocakavuk, Emre , Ducray, François , Simonelli, Matteo , Yu, James B. , Hervey‐Jumper, Shawn L. , McKhann, Guy M. , Canoll, Peter , Ostrom, Quinn T. , Iwamoto, Fabio M., Mehta, Minesh P. , Wang, Tony J. C.

Journal of Clinical Oncology | August 12, 2026 | Volume: No volume available | Issue: No issue available | Pages: No page available

10.1200/jco-25-01846 Get It

PURPOSE Age ≥40 years is regarded as a high-risk feature and an indication for adjuvant chemoradiotherapy for patients with lower-grade glioma in clinical practice guidelines. It is unclear whether age remains a relevant prognostic factor for contemporary definitions of lower-grade gliomas in the molecular era. METHODS The Prospective Gliomas Research (PROGRES) database contains individual patient-level data from 11 prospective clinical trials or observational registries of histologically defined lower-grade 2-3 oligodendroglioma or astrocytoma. We determined the association of age (18-39 years v ≥40 years) with progression-free survival (PFS) stratified by isocitrate dehydrogenase 1 or 2 ( IDH1/2 ) status, using log-rank tests and Cox regression models. We validated our findings in a separate multi-institutional retrospective cohort (Retrospective Glioma Research [REGRES] database). RESULTS We identified 1,619 and 1,292 eligible patients in the PROGRES and REGRES cohorts, respectively. IDH -wildtype tumors were more common in patients 40 years and older (38% v 5%, odds ratio: 11.3 [95% CI, 6.5 to 19.7]). Age was associated with PFS in IDH -wildtype (5-year PFS for ≥40 v 18-39 years: 6% v 24%, hazard ratio [HR], 1.74 [95% CI, 1.21 to 2.50]) but not in IDH -mutant glioma (60% v 59%, HR, 0.89 [95% CI, 0.76 to 1.05], P interaction < .001). In IDH -wildtype tumors, older age predicted aggressive molecular features, including TERT promoter mutation (65% v 28%), EGFR amplification (41% v 15%), and chromosome +7/–10 alteration (57% v 25%). In a pooled analysis of four clinical trials, age was not predictive of a benefit from chemoradiotherapy versus radiotherapy alone for IDH -mutant glioma. CONCLUSION In the absence of additional clinical or molecular risk factors, age alone should not be considered an indication for administration or deferral of adjuvant treatment. Practice guidelines should be revised to reflect contemporary prognostic factors in the molecular era.
A shared injury–homeostasis gradient in the human CSF proteome across neurological disease
Mansouri, Alireza , Mikolajewicz, Nicholas , Riviere-Cazaux, Cécile , Tuohy, Kyle , Kumar, Rahul , Miller, Alexandra, Ahluwalia, Manmeet S. , Bettegowda, Chetan , Burns, Terry, Mansouri, Alireza , Ahluwalia, Manmeet S , Kumar, Rahul , Bettegowda, Chetan , Tuohy, Kyle , Ranganathan, Sruthi , Boutros, Paul C. , Kislinger, Thomas

No container title available | August 11, 2026 | Volume: No volume available | Issue: No issue available | Pages: No page available

10.21203/rs.3.rs-10480838/v1 Get It

Abstract Cerebrospinal fluid (CSF) is the biofluid most proximal to the central nervous system (CNS), yet its proteomic organization across neurological disease remains unresolved. We assembled a meta-atlas of 35 CSF proteomic datasets (2016–2026) comprising 10,560 quality-controlled samples spanning neurodegenerative, neuroinflammatory, neuro-oncological, infectious and structural-injury contexts. Meta-analysis of cross-cohort detection defined a 747-protein core mass-spectrometry-accessible CSF proteome that generalizes to held-out cohorts. We derived thirteen consensus meta-programs that transfer across independent cohorts and span the major neural, barrier, immune and plasma compartments. Unexpectedly, these programs are dominated by a single axis of variation opposing complement- and plasma-associated inflammation against neuronal-synaptic homeostasis. This injury–homeostasis axis is diagnosis-spanning and tracks clinical severity and disease activity across diverse neurological conditions. We show that a two-protein C5–NRCAM model can approximate the injury–homeostasis axis, bridging deep proteomic profiling toward bedside assessment.
Intercellular adhesion molecule 1 links glioblastoma biology to a scalable prognostic model integrating clinical, imaging, and molecular features
Gandhi, Shreya, Ocaña-Tienda, Beatriz , Bettencourt, Manuel M., Singh, O, Devaraja, Kaviya , Irish, Emily R., Molina-García, David , Karimi, Shirin, Sosa, Julio , McIntyre, Ian, Gao, Andrew , Ramos-González, Ana, Asenjo, Beatriz , Flores-Rial, María Pino, Aldape, Kenneth , Santos, Carlos, Velásquez, Carlos, Mansouri, Alireza, Zadeh, Gelareh, Singh, Olivia S, Pérez-Beteta, Julián , Asenjo, Beatriz , Sánchez-Gómez, Pilar , Aldape, Kenneth D, Santos, Carlos , Mansouri, Alireza , Zadeh, Gelareh , Mansouri, Sheila , Mamatjan, Yasin , Hernández‐Laín, Aurelio , Drummond, Katharine Jann , Parney, Ian F. , Velásquez, Carlos , Mansouri, Alireza , Pérez‐García, Víctor M. , Mansouri, Sheila

Neuro-Oncology Advances | July 10, 2026 | Volume: 8 | Issue: 1 | Pages: No page available

10.1093/noajnl/vdag182 Get It

Abstract Background Glioblastoma (GB) exhibits marked tumor microenvironmental heterogeneity, contributing to both therapy resistance and poor survival outcomes. Intercellular adhesion molecule 1 (ICAM1) is an inflammation-associated adhesion molecule implicated in immune-stromal interactions, but its clinical and biological significance in GB remains incompletely defined. Methods We performed ICAM1 immunohistochemistry, bulk RNA sequencing, DNA methylation analysis, single-nucleus RNA sequencing, and preoperative MRI-derived morphologic feature analysis across multi-institutional cohorts of treatment-naïve IDH-wildtype GB. Results High ICAM1 expression at both transcript and protein levels is associated with shorter overall survival, particularly within the mesenchymal transcriptional subtype. ICAM1 expression is inversely associated with promoter methylation. Single-nucleus RNA-sequencing analysis shows that ICAM1-high tumors are enriched for mesenchymal, hypoxia, stress-associated, and immunosuppressive myeloid programs, suggesting that ICAM1 reflects a multicompartment inflammatory tumor ecosystem. ICAM1 expression, tumor surface irregularity, and patient age are independently prognostic and minimally correlated, capturing complementary clinical, imaging, and molecular features of GB biology. When combined, our Clinical-Imaging-Molecular (CIM) framework refines outcome prediction across independent GB cohorts using routinely available clinical data, conventional imaging, and standard immunohistochemistry. Conclusions ICAM1 characterizes an immune-remodeled, stress-adapted GB ecosystem associated with poor clinical outcomes. Integrating patient age, surface irregularity, and ICAM1 expression yields a scalable and clinically accessible prognostic framework for GB, supporting tailored outcome prediction, particularly in low- and middle-resource settings without routine access to advanced molecular profiling.
A phase 0 clinical trial to evaluate the neuropharmacological profile of posaconazole for glioblastoma
Mansouri, Alireza, Filho, Leonardo De Macedo, Tufano, Emily , Laukhuff, Harrison , Zacharia, Brad, Neighbors, Jeffrey , Green, Michele, Derosia, Nicole , Sun, Dongxiao, Bhanja, Debarati , Tuohy, Kyle , Connor, J F, Aregawi, Dawit , Glantz, Michael, Zadeh, Gelareh, Mansouri, Alireza , Filho, Leonardo de Macêdo , Mansouri, Alireza , de Macêdo Filho, Leonardo J M , Zacharia, Brad E , Connor, James , Aregawi, Dawit G , Glantz, Michael J , Zadeh, Gelareh , Zacharia, Brad E. , Neighbors, Jeffrey D. , Tuohy, Kyle

Neuro-Oncology Advances | July 1, 2026 | Volume: 8 | Issue: 1 | Pages: No page available

10.1093/noajnl/vdag174 Get It

Abstract Background Glioblastoma (GBM) is the most common malignant primary brain tumor and is associated with a poor prognosis. Repurposed posaconazole (PCZ) has demonstrated efficacy in vitro by targeting key metabolic pathways. The aim of this study was to determine the neuropharmacological profile of PCZ in patients with GBM through a Phase 0 first-in-human trial for this indication (NCT04825275). Methods We conducted an open-label, non-randomized, parallel-arm trial in participants with primary or recurrent GBM. Patients in the treatment arm received oral PCZ for 7-10 days presurgically to achieve steady-state concentrations. Microdialysis catheters were implanted to measure interstitial drug levels. Postoperative tissue and fluid samples were analyzed to evaluate PCZ pharmacokinetics (mass spectrometry) and pharmacodynamics, including vascular density, apoptosis, and metabolite concentrations (lactate and pyruvate) compared to controls. Results The trial was closed early due to slow accrual, enrolling 2 participants in the PCZ arm and three in the control arm. No drug-related safety issues were observed. Although PCZ was undetectable in microdialysate fluid, it accumulated in tumor tissue, with concentrations showing an association with CD31-measured endothelial content. PCZ-treated tumors exhibited trends toward lower BCL2 expression indicative of increased apoptosis, and significantly lower pyruvate levels in the tumor periphery compared to controls. Plasma lactate levels in treated patients normalized to control levels over 24 h. Conclusions Despite limited accrual, this trial provides the first clinical evidence that oral PCZ accumulates in human GBM tissue and shows preliminary signals of metabolic modulation. These findings provide biological rationale warranting further clinical investigation, potentially utilizing direct tissue sampling rather than microdialysis.
A hitchhiker’s guide to cerebrospinal fluid biomarkers for neuro-oncology
Riviere-Cazaux, Cécile , Keough, Michael B. , Schulz, Sebastian C, Warrington, Arthur E. , Ruff, Michael W. , Sanai, Nader , Campian, Jian , Kizilbash, Sani H. , Zadeh, Gelareh , Khasraw, Mustafa , Kessler, Tobias , Cahill, Daniel P. , Mansouri, Alireza , Kizilbash, Sani H , Zuccato, Jeffrey , Kumar, Rahul Robaish , Schulz, Sebastian C, Ellingson, Benjamin M. , Parney, Ian F. , Khasraw, Mustafa , Sener, Uğur , Mansouri, Alireza , Burns, Terry C.

Neuro-Oncology | December 27, 2024 | Volume: 27 | Issue: 5 | Pages: 1165-1179

10.1093/neuonc/noae276 Get It

Abstract Cerebrospinal fluid (CSF) has emerged as a valuable liquid biopsy source for glioma biomarker discovery and validation. CSF produced within the ventricles circulates through the subarachnoid space, where the composition of glioma-derived analytes is influenced by the proximity and anatomical location of sampling relative to tumor, in addition to underlying tumor biology. The substantial gradients observed between lumbar and intracranial CSF compartments for tumor-derived analytes underscore the importance of sampling site selection. Moreover, radiographic features, such as tumor-CSF contact and blood-brain barrier disruption, are critical covariates that may affect biomarker detection and the abundance of plasma-derived analytes in CSF, respectively. Longitudinal intracranial CSF sampling, enabled by access devices like Ommaya reservoirs, may offer a window into treatment response and disease progression, though variability in analyte yield, sample volumes, and the dynamic effects of surgical resection pose challenges. This review critically evaluates the anatomic, radiographic, and longitudinal factors, or “time-space continuum,” that impact glioma CSF biomarker abundance. Practical considerations for longitudinal CSF biobanking, including access device placement and collection, are also reviewed. Key takeaways and recommendations for CSF glioma biomarker discovery and validation are provided as a “hitchhiker’s guide” based on our collective experience, along with resources for investigators aiming to develop CSF biobanking at their institutions.
Suicidal ideation and attempts in brain tumor patients and survivors: A systematic review
Mofatteh, Mohammad , Mashayekhi, Mohammad Sadegh , Arfaie, Saman , Alvi, Mohammed Ali , Sader, Nicholas , Antonick, Violet, Mansouri, Alireza , Liao, Xuxing , Maestro, Rolando F. Del , Zadeh, Gelareh , Ashkan, Keyoumars, Alvi, Mohammed Ali , Mansouri, Alireza , Zadeh, Gelareh , Chen, Yimin , Malhotra, Armaan Kush , Fatehi, Mostafa , Das, Sunit , McIntyre, Roger S. , Turecki, Gustavo , Cohen‐Gadol, Aaron , Sader, Nicholas

Neuro-Oncology Advances | May 12, 2023 | Volume: 5 | Issue: 1 | Pages: No page available

10.1093/noajnl/vdad058 Get It

Abstract Background Subsequent to a diagnosis of a brain tumor, psychological distress has been associated with negative effects on mental health as well as suicidality. The magnitude of such impact has been understudied in the literature. We conducted a systematic review to examine the impact of a brain tumor on suicidality (both ideation and attempts). Methods In accordance with the PRISMA guidelines, we searched for relevant peer-reviewed journal articles on PubMed, Scopus, and Web of Science databases from inception to October 20, 2022. Studies investigating suicide ideation and/or attempt among patients with brain tumors were included. Results Our search yielded 1,998 articles which were screened for eligibility. Seven studies consisting of 204,260 patients were included in the final review. Four studies comprising 203,906 patients (99.8%) reported elevated suicidal ideation and suicide attempt incidence compared with the general population. Prevalence of ideation and attempts ranged from 6.0% to 21.5% and 0.03% to 3.33%, respectively. Anxiety, depression, pain severity, physical impairment, glioblastoma diagnosis, male sex, and older age emerged as the primary risk factors associated with increased risk of suicidal ideation and attempts. Conclusion Suicidal ideation and attempts are increased in patients and survivors of brain tumors compared to the general population. Early identification of patients exhibiting these behaviors is crucial for providing timely psychiatric support in neuro-oncological settings to mitigate potential harm. Future research is required to understand pharmacological, neurobiological, and psychiatric mechanisms that predispose brain tumor patients to suicidality.
Natural History of Brachial Plexus, Peripheral Nerve, and Spinal Schwannomas
Pennington, Zach , Ochuba, Arinze , Mansouri, Alireza , Belzberg, Allan J. , Mansouri, Alireza , Pennington, Zach , Lubelski, Daniel , Azad, Tej Deepak , Blakeley, Jaishri O.

Neurosurgery | September 7, 2022 | Volume: 91 | Issue: 6 | Pages: 883-891

10.1227/neu.0000000000002118 Get It

BACKGROUND: Management of sporadic schwannomas is often dictated by a patient's clinical presentation and the tumor's behavior. For patients who are managed nonsurgically, there are little data available about the expected natural history. OBJECTIVE: To evaluate the natural history and growth patterns of extracranial schwannomas including tumors of the distal peripheral nerves, spine, and brachial plexus. METHODS: A retrospective review was performed to identify patients with nonsyndromic extracranial schwannomas at a single tertiary care institution diagnosed between 2002 and 2019. Patient data and tumor characteristics including volume were recorded. RESULTS: Two hundred twenty-seven patients were identified (mean age 51 years, 42% male, average of 27.8-month follow-up). Tumor location was distal peripheral nerve in 82, brachial plexus in 36, and paraspinal in 109. At the time of diagnosis, peripheral lesions were significantly larger than spinal (59 m 3 vs 13 cm 3 ) and brachial plexus lesions (15 cm 3 ). Distinct growth patterns were seen with both distal peripheral nerve and spinal lesions; 34/82 peripheral nerve lesions had fast growth (β = 0.176%/day), and 48 had slow growth (β = 0.021%/day; P < .01). Spinal schwannomas similarly had 30 fast-growing (β = 0.229%/day), 16 moderate-growing (β = 0.071%/day), and 63 slow-growing (β = 0.022%/day; P = .03) subtypes. The brachial plexus had relatively homogeneous growth patterns (β = 0.065%/day). Females had 2.9 times greater odds of having the fast-growing subtype. CONCLUSION: Distinct growth patterns were seen in extracranial sporadic schwannomas based on tumor location and patient demographics. Fast (>80% volume change per year) vs slow (5%-10% per year) tumor growth can often be ascertained within 2 follow-up images. Awareness of these patterns might have implications for patient counseling and therapeutic decision-making.
Designing Clinical Trials for Combination Immunotherapy: A Framework for Glioblastoma
Singh, Kirit , Batich, Kristen A. , Wen, Patrick Y. , Bagley, Stephen , Lim, Michael , Platten, Michael , Colman, Howard , Ashley, David M. , Chang, Susan M. , Rahman, Rifaquat , Mansouri, Alireza , Reardon, David A. , Sahebjam, Solmaz , Simes, John, Berry, Donald A. , Zadeh, Gelareh , Cloughesy, Tim, Piantadosi, Steven , Weller, Michael , Heimberger, Amy B. , Tan, Aaron C. , Platten, Michael , Colman, Howard , Galanis, Evanthia , Berry, Donald , Mehta, Minesh P , Piantadosi, Steven , Weller, Michael , Khasraw, Mustafa , Mansouri, Alireza , Wen, Patrick Yung , Galanis, Evanthia , Puduvalli, Vinay K. , Sampson, John Howard , Mehta, Minesh P. , Heimberger, Amy B. , Khasraw, Mustafa , Simes, Robert John

Clinical Cancer Research | September 24, 2021 | Volume: 28 | Issue: 4 | Pages: 585-593

10.1158/1078-0432.ccr-21-2681 Get It

Abstract Immunotherapy has revolutionized treatment for many hard-to-treat cancers but has yet to produce significant improvement in outcomes for patients with glioblastoma. This reflects the multiple and unique mechanisms of immune evasion and escape in this highly heterogeneous tumor. Glioblastoma engenders profound local and systemic immunosuppression and is remarkably effective at inducing T-cell dysfunction, posing a challenge to any immunotherapy-based approach. To overcome these mechanisms, multiple disparate modes of immune-oriented therapy will be required. However, designing trials that can evaluate these combinatorial approaches requires careful consideration. In this review, we explore the immunotherapy resistance mechanisms that have been encountered to date and how combinatorial approaches may address these. We also describe the unique aspects of trial design in both preclinical and clinical settings and consider endpoints and markers of response best suited for an intervention involving multiple agents.
Early phase clinical studies of AR ‐42, a histone deacetylase inhibitor, for neurofibromatosis type 2‐associated vestibular schwannomas and meningiomas
Welling, D. Bradley , Collier, Katharine A. , Burns, Sarah S. , Oblinger, Janet L. , Shu, Edina , Miles‐Markley, Beth A., Slone, H. Wayne, Neff, Brian A., Jackler, Robert K. , Mortazavi, Amir , Chang, Long‐Sheng , Mansouri, Alireza , Jackler, Robert K , Mansouri, Alireza , Hofmeister, Craig C. , Makary, Mina S. , Blakeley, Jaishri O. , Mansouri, Sheila

Laryngoscope Investigative Otolaryngology | August 20, 2021 | Volume: 6 | Issue: 5 | Pages: 1008-1019

10.1002/lio2.643 Get It

Abstract Objectives Two pilot studies of AR‐42, a pan‐histone deacetylase inhibitor, in human neurofibromatosis type 2 (NF2), vestibular schwannomas (VS), and meningiomas are presented. Primary endpoints included safety, and intra‐tumoral pharmacokinetics (PK) and pharmacodynamics (PD). Methods Pilot 1 is a subset analysis of a phase 1 study of AR‐42 in solid tumors, which included NF2 or sporadic meningiomas. Tumor volumes and treatment‐related adverse events (TRAEs) are reported (NCT01129193). Pilot 2 is a phase 0 surgical study of AR‐42 assessing intra‐tumoral PK and PD. AR‐42 was administered for 3 weeks pre‐operatively. Plasma and tumor drug concentrations and p‐AKT expression were measured (NCT02282917). Results Pilot 1: Five patients with NF2 and two with sporadic meningiomas experienced a similar incidence of TRAEs to the overall phase I trial. The six evaluable patients had 15 tumors (8 VS, 7 meningiomas). On AR‐42, tumor volume increased in six, remained stable in eight, and decreased in one tumor. The annual percent growth rate decreased in eight, remained stable in three, and increased in four tumors. Pilot 2: Four patients with sporadic VS and one patient with meningioma experienced no grade 3/4 toxicities. Expression of p‐AKT decreased in three of four VS. All tumors had higher AR‐42 concentrations than plasma. Conclusions AR‐42 is safe. Tumor volumes showed a mixed response, but most slowed growth. On a 40‐mg regimen, drug concentrated in tumors and growth pathways were suppressed in most tumors, suggesting this may be a well‐tolerated and effective dose. A phase 2 study of AR‐42 for NF2‐associated tumors appears warranted. Level of Evidence 1b, 4.
Systematic review of combinations of targeted or immunotherapy in advanced solid tumors
Wen, Patrick Y. , Lim, Michael , Platten, Michael , Colman, Howard , Ashley, David M. , Chang, Susan M. , Mansouri, Alireza , Khagi, Simon , Heimberger, Amy B. , Reardon, David A. , Sahebjam, Solmaz , Simes, John, Antonia, Scott , Berry, Don, Tan, Aaron C. , Platten, Michael , Heimberger, Amy B. , Khasraw, Mustafa , Mansouri, Alireza , Bagley, Stephen , Wen, Patrick Yung , Colman, Howard , Wick, Wolfgang , Chang, Susan Marina , Galanis, Evanthia , Mehta, Minesh P. , Puduvalli, Vinay K. , Simes, Robert John , Berry, Donald A. , Khasraw, Mustafa

Journal for ImmunoTherapy of Cancer | July 2, 2021 | Volume: 9 | Issue: 7 | Pages: e002459

10.1136/jitc-2021-002459 Get It

With rapid advances in our understanding of cancer, there is an expanding number of potential novel combination therapies, including novel–novel combinations. Identifying which combinations are appropriate and in which subpopulations are among the most difficult questions in medical research. We conducted a Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA)-guided systematic review of trials of novel–novel combination therapies involving immunotherapies or molecular targeted therapies in advanced solid tumors. A MEDLINE search was conducted using a modified Cochrane Highly Sensitive Search Strategy for published clinical trials between July 1, 2017, and June 30, 2020, in the top-ranked medical and oncology journals. Trials were evaluated according to a criterion adapted from previously published Food and Drug Administration guidance and other key considerations in designing trials of combinations. This included the presence of a strong biological rationale, the use of a new established or emerging predictive biomarker prospectively incorporated into the clinical trial design, appropriate comparator arms of monotherapy or supportive external data sources and a primary endpoint demonstrating a clinically meaningful benefit. Of 32 identified trials, there were 11 (34%) trials of the novel–novel combination of anti-programmed death 1 (PD-1)/programmed death ligand 1 (PD-L1) and anti-cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) therapy, and 10 (31%) trials of anti-PD-1/PD-L1 and anti-vascular endothelial growth factor (VEGF) combination therapy. 20 (62.5%) trials were phase II trials, while 12 (37.5%) were phase III trials. Most (72%) trials lacked significant preclinical evidence supporting the development of the combination in the given indication. A majority of trials (69%) were conducted in biomarker unselected populations or used pre-existing biomarkers within the given indication for patient selection. Most studies (66%) were considered to have appropriate comparator arms or had supportive external data sources such as prior studies of monotherapy. All studies were evaluated as selecting a clinically meaningful primary endpoint. In conclusion, designing trials to evaluate novel–novel combination therapies presents numerous challenges to demonstrate efficacy in a comprehensive manner. A greater understanding of biological rationale for combinations and incorporating predictive biomarkers may improve effective evaluation of combination therapies. Innovative statistical methods and increasing use of external data to support combination approaches are potential strategies that may improve the efficiency of trial design. Designing trials to evaluate novel–novel combination therapies presents numerous challenges to demonstrate efficacy in a comprehensive manner. A greater understanding of biological rationale for combinations and incorporating predictive biomarkers may improve effective evaluation of combination therapies. Innovative statistical methods and increasing use of external data to support combination approaches are potential strategies that may improve the efficiency of trial design.